Accelerated Bridge Construction Earns Hamilton Top Honors

Accelerated bridge construction requires that certain materials be fabricated off-site and assembled without disruption to traffic. The Oregon Department of Transportation used this construction method on the Isthmus Slough East Approach Bridge project. Prior to closure and demolition, Hamilton, the contractor, constructed the entire substructure underneath the existing bridge. The new substructure required driving more than 20 pilings to depths ranging from 90 ft. to 120 ft. Other project elements prepared in advance included precast slab erection, precast barriers, drainage systems, utility protection and the construction of two major bridge works. The bridge works were installed to allow for the positioning of two cranes and pile driving equipment used for the project. The efforts of the project team to find and communicate new ways to improve efficiency resulted in the bridge being completed ahead of schedule by seven days. The cost savings and the least amount of traffic disruption make accelerated bridge construction a fast effective way to solve problems.